2000 s-Blazer 4.3 awd front drive problem

I just bought this (really a bravada) 5 day ago @ a local chevy dealer "as-is" with 111. Mi. The service awd light was on and I figured it was just one of those sensor or something like that problems that I could look at or have looked at soon after. Well, soon after was too long and had to have it towed home 2 days later. Everything seemed fine for the first 2 days. Drove to and from work left to pick up stepdaughter from work and started to smell burning oil or gear lube smell. It was starting to get dark so just had it towed.(Forgot to mention awd light was out)
after getting it in the garage (it still moves)and getting under it this is what I found:
drivers side inner cv boot has slung a large amount of grease out but not from the boot as in a hole rather like next to it. Also the seal where the front drive shaft goes in is leaking hence the gear lube smell (burning on the cross over pipe).
so I guess my question is, is there something that would cause both things to fail at the same time?
does the front diff build enough pressure to force out the grease and oil?
if anyone has run across this or anyone with any ideas it would be most helpfull